The influence of substituents on the properties of crystalline polyhydrocarbons. I. Methyl‐substituted arylpropene and arylbutene polymers

Abstract

Abstract The new alpha olefins 2‐allyl‐ p ‐xylene, 4‐allyl‐ o ‐xylene, 5‐allyl‐ m ‐xylene, 4‐( o ‐tolyl)‐1‐butene and 4‐( p ‐tolyl)‐1‐butene were prepared. These olefins, in addition to the known ortho, meta and para allyltoluenes, have polymerized, using aluminum alkyl titanium chloride catalyst, to crystalline polymers. Physical properties of these polymers, both as powder and molded sample, have been studied. Melt temperatures ( T m ) and glass transition temperatures ( T g ) have been determined using differential thermal analysis, dynamic modulus measurements, and dilatometric measurements; observations on the birefringent melting behavior were also noted. The effects of both olefin chain length and substitution of methyl groups in the ortho, meta, and para position, respectively, on the properties of these polymers have been interpreted according to present concepts. The results are in general agreement with corresponding data for isotactic methyl‐substituted polystyrenes. Substitution in the ortho position raises both transition temperatures considerably, while meta and para substitution cause only smaller effects.